Various kinds of nozzles have been used in the past on dispenser modules for melted thermoplastic materials such as adhesives and other melted materials. Such heated liquid materials are often referred to as "hot melt materials" and are materials which are solid at room or ambient temperature but, when heated, convert to a liquid state.
The nozzle configuration and adjustability is dependent upon the particular application for which the nozzle is to be used. It is known to use nozzles which may be rotatably adjustable about an axis and which have nozzle outlet orifices which direct a stream of melted fluid material at some predetermined angle which is inclined to the axis of rotation of the body of the nozzle.
An example of such prior nozzle is shown in U.S. Pat. No. 4,469,248 issued to P. J. Petrecca. The nozzle shown in the Petrecca patent is attached to a threaded outlet nipple of a fluid dispenser module by a connector nut which is tightened on the nipple until a rotatable body of the nozzle is drawn into such tight contact with an end of the outlet nipple that the nozzle body cannot be rotated without slightly loosening the nut. Adjusting such nozzle requires two tools, with one tool engaging the nut and the other tool engaging the rotary nozzle body. To adjust the nozzle the nut is first loosened slightly with a wrench and the nozzle body is moved to the desired rotational position with a second tool such as a screwdriver. The nozzle body is then held in the desired adjusted position by the screwdriver while the nut is retightened on the outlet nipple with the wrench.
Once the nut is securely tightened, the nozzle body is drawn tightly against the end of the nipple, thereby locking the nozzle body in the adjusted position and preventing it from turning unless the nut is loosened.
In addition the rotary nozzle body in the Petrecca patent is secured to the connector nut by a lock ring which fits in an annular groove in the nut and engages a radially outwardly extending flange on nozzle body. If the nut is tightened too far on the outlet nipple, the lock ring can become deformed, thereby causing leakage between the nut and the nozzle body.
The present invention eliminates the need for using two tools by providing such an interface between the nut the nozzle body, and the outlet nipple that the nozzle body is spaced from the outlet nipple so that it can be rotated with a single tool without loosening the nut and without requiring a second tool to loosen and tighten the nut. In the present invention the rotary nozzle body is retained by a radially inwardly extending flange on the nut rather than a lock ring and a resilient O-ring seal is located under radial compression between the nozzle body and the nut. The radially inwardly extending flange on the nut contacts the end of the outlet nipple and prevents overtightening of the nut to cause contact between the nipple and the nozzle body.